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A two dimensional spectral/spatial cyclic shift (2D-CS) optical code division multiple access (OCDMA) systems is proposed for a potentially next generation passive optical network (NG-PON) implementation called (2D-CS NG-OCDMA-PON) system. The2D-CS proposed code is characterized by a high capacity and a zero cross correlation property leads to completely eliminating the multiple access interference (MAI) effect that is considered as the main OCDMA system drawback. Firstly, the 2D-CScode construction is investigated from 1D-CS code. Secondly, a system description is provided by exhibiting the transmitter and receiver architecture in the PON context. Analytical analysis reveals that our proposed 2D-CScode outperforms similar codes such as perfect difference (2D-PD) and dynamic cyclic shift (2D-DCS) codes in terms of spectral efficiency, simultaneous network subscribers and data bit rate. In addition, based on numerical analysis 2D-CS NG-OCDMA-PON system shows a good system performance by means of avery low BER and a high Qfactor values equal to10 −26 and 10.41 dB, respectively. Likewise, for four users and free-amplification the achievable reach ability distance of the NG-OCDMA-PON system is 63.21 km, 43.57 km and 33.2 km while Q-factor is equal to 6 dB at a bit rate of 622Mb/s, 1Gb/s and 1.5 Gb/s, respectively. On the other side, according to the system setup the number of single mode fiber (SMF) is reduced to the half compared to other 2D-OCDMA-PON systems based on enhanced multi diagonal (EMD) and single weight ZCC (SWZCC) codes.

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This paper presents for non-coherent Optical Code Division Multiple Access (OCDMA) systems a new optical code namely Two-Dimensional Half Spectral/Spatial Zero Cross Correlation (2D-HSSZCC) code based on a One-Dimensional Zero Cross Correlation (1D-ZCC) code already developed using block matrices characterized by a high capacity. The results of simulation show that the use of the new (2D-HSSZCC) code eliminates totally the Multiple Access Interferences (MAI) due to the zero cross correlation flexibility, and less complexity of the code construction which produces a very low bit error rate of closely (4×10−18) at 1 Gbps for four users with a low power source of −12.60 dBm to reach a high data rate and high number of simultaneous users upper to closely 149, save an effective power around −1.35 dBm, −3.3d Bm compared between those provides by (Two-Dimensional dynamic cyclic shift (2D-DCS) code and Two-Dimensional Dimensional Diluted Perfect Difference (2D-DPD) and (1D-ZCC) code, and increase the cardinality percentage upper to 1.58, 2.19, 2.33 and 3.9 times comparing to (2D-DCS) code, 2D-DPD code, 1D-ZCC code and Two-Dimensional Flexible Cross Corelation/Modified Double Weight (2D-FCC/MDW) code. On the other hand, 2D-HSSZCC code is comparied with other codes which has it same property namely Two-Dimensional zero cross correlation/multi diagonal (2D-ZCC/MD) and (2D-MD) codes where the increased percentage in system capacity was 1.38 and 1.05 times, respectively. Finally, the results obtained in part 1 (with Matlab software) were confirmed and validated with the Optisystem software, the proposed system gave a better BER minimum value around 10−21 and a maximum value of the Q factor of around 9.4 at 622 Mbps of data rate when the number of simultaneous users increases.

In this paper, a novel zero cross correlation (ZCC) code is proposed for spectral amplitude coding-optical code division multiple access (SAC-OCDMA) systems. The code construction method starts from the identity matrix and has several benefits summarized in both the code simplicity and flexibility. The proposed code presents also an adapted (or accepted) code length for SAC-OCDMA systems and a high SNR value that reaches respectively 3.18 and 1.84 times of the system capacity comparing to other existed codes such as modified quadratic congruence (MQC) and modified double weight (MDW) codes.